We consider the problem of leader election among mobile agents
operating in an arbitrary network modeled as an undirected graph.
Nodes of the network are unlabeled and all agents are identical. Hence the
only way to elect a leader among agents is by exploiting asymmetries
in their initial positions in the graph. Agents do not know the graph or
their positions in it, hence they must gain this knowledge
by navigating in the graph and share it with other agents to accomplish
leader election. This can be done using meetings of agents, which is
difficult because of their asynchronous nature:
an adversary has total control over the speed of agents. When can a leader
be elected in this adversarial scenario and how to do it?
We give a complete answer to this question by characterizing all initial
configurations for which leader election is possible and by constructing
an algorithm that accomplishes leader election for all configurations for
which this can be done.
This is joint work with Andrzej Pelc.
Intervenant: Dariusz Dereniowski